Tech Tip: The quality is cheap (low resolution/poor quality) on Surveillance cameras that use RJ11 "telephone" connectors. Medium quality units use RCA connecors for the video & Better units use BNC connectors for the video signals. When you are unhappy with stuff from the "cheap club" store--remember: "we told you not to waste your money" on throw-away products!

above adapters for using stereo audio cables to extend power to security cameras

Tech Tip: Horizontal Interference Lines (often moving up the picture) in a display from a security system--displayed on a flat-screen TV--can be caused by a ground loop problem. The ground loop occurs because Cable TV and DVD and VCR's etc have grounds that are not at exactly the same potential! (different lengths of cords and in different rooms and not everything plugged into the same AC electrical outlet).
If the TV is connected to Cable TV--the first thing to try is to disconnect the Cable TV wire to see if the interference disappears--if it disappears--then add a CR75-504 RF ground loop isolation transformer to the Cable TV coax.
If the interference only occurs with the security camera connected--A solution is to add a baseband video ground loop isolator on the security camera output; these are expensive and most suppliers don't keep these in stock!
An alternative (cheap) solution is use an individual power supply (not the central power supply for the security system) to power the offending camera AND to plug the power supply for that camera into a grounded-to-ungrounded (3-prong to 2-prong) adaptor (ground wire not connected). If the camera is mounted on a metal polebarn building--it may also be necessary to mount the camera on plastic or wood to isolate the camera housing from the metal of the building.